/**
* @description: 产生任意随机数
* @param {*开始值} minNum
* @param {*结算值} maxNum
* @return {*返回一个随机数}
* @author: CHY
*/
function randomNum(minNum, maxNum) {
    switch (arguments.length) {
        case 1: return parseInt(Math.random() * minNum + 1); break;
        case 2: return parseInt(Math.random() * (maxNum - minNum + 1) + minNum); break;
        default: return 0; break;
    }
}